Brain Imaging in Schizophrenia

Three key imaging techniques that have revealed brain abnormalities in people with schizophrenia are magnetic resonance imaging, computed tomography, and positron emission tomography.

What is Magnetic Resonance Imaging?

Magnetic resonance imaging (MRI) studies have shown that the ventricles the cavities inside the brain that contain cerebrospinal fluid may be enlarged in people with schizophrenia . For example, a study of identical twins who were discordant for schizophrenia found that virtually all affected twins had larger cerebral ventricles than their unaffected twins.

What is Computed Tomography? (CT)

Computed tomography (CT) is effective in revealing bone structures and areas of dense tissue. CT scans have shown that people with schizophrenia have enlarged ventricles and some reduction in the volume of the cortex. Other studies have reported abnormalities in cerebral symmetry and brain density. While some studies have also correlated the presence of CT scan abnormalities with various symptoms, these results are unconfirmed. CT scans have also been inconclusive in establishing whether brain abnormalities seen at the onset of schizophrenia progress during the illness.

What is Positron Emission Tomography? (PET)

Positron emission tomography (PET) measures metabolic activity and can show how different parts of the brain are functioning. As you know, the frontal lobes and cerebral cortex are involved in cognition and executive functions (see Figure 5‑4). Although some PET scans have shown that people with schizophrenia have hypoactivity in the frontal lobes and hyperactivity in the basal ganglia relative to the cerebral cortex, these results have not been widely replicated. PET scans have also produced conflicting results regarding whether people with schizophrenia have an increased number of D2 receptors in the basal ganglia.